SHARK PICTURE: Most Complete Great White Fossil Yet

March 12, 2009—This four-million-year-old fossil has taken some of the bite out of the great white shark's supposedly menacing ancestry, a new study finds.

The specimen—which includes part of the spinal column, the head, jaws lined with 222 teeth—is the most complete fossil known of an ancient great white shark.

Scientists had long assumed that great whites—which can reach lengths of 20 feet (6.1 meters)—were close kin of the prehistoric "megatooth" sharks, frightening creatures that grew up to 50 feet (15.2 meters) long and had jaws more than 9 feet (2.7 meters) wide.

But a new look at the fossil suggests that great whites are more closely related to the less fearsome and smaller mako shark, which belonged to a genus that still exists today.

If true, megatooths and great white sharks may have hit jumbo size independently, said study lead author Dana Ehret, a graduate student at the Florida Museum of Natural History.